Coal washing machine



Oct. 17, 1933. G, ON 1,931,390

COAL WASHING MACHINE Filed Dec. 22, 1931 2 Sheets-Sheet l $607190 WbrZZw Z116 4 z 1933- G. NORTON 1,931,390

COAL WASHING MACHINE Filed Dec. 22, 1931 2 sheets-shed 2 $90256 JVZr$m fiw y n u lbrne ya' Patented Oct. 17, 1933 COAL ,WASHING,MACHINE George Norton, Handsworth, England Application December 22, 1931, Serial No. 582,593,

l and in Great Britain December 31, 1930 3 Claims. (01. 209- 496) This invention relates to coal washing machines of the type in which the coal during the process of washing is passed over a bed of perforated plates or bars and issubjected to the pulsating action of water acting through the bed.

7 In this type of-machine theeflicien'cy of the washing depends on maintaining, in conjunction with suitable water currents, a correct depth of stone or shale underneath the coal. Since this bed is being continually added to by the debris-chiefly shalerem0ved from the coal a means of drawl ing off the surplus shale is of necessity provided.

For controlling the depth of the shale bed various means have been adopted, the mostusual method being to allow the surplus shale to work its way through a pair of adjustable gate openings, one at each endiof the washing bed; it being the duty of the attendant to examine the bed periodically-usually by prodding to ascertain its depth and densityand adjust the hand gates so as to maintain the required conditions.

In addition to the system of hand control referred to above, various methods. have been adopted for automatically regulating the egress of the shale by means of mechanically, electrically, and pneumatically controlled devices. The present. invention relates tov the mechanically operated rotary gatetype of control gear.

The invention has for one of its objects to provide an improved form of control'gear for a rotary gate in which'the motion is only transmittedto the gear when a movement of the gate is required.

Another object of the invention is to provide a rotary gate operated by a pawl and ratchet gear so arranged that theoperating pawl is. al-

ways fully in mesh with the ratchet wheel but is only operated when a movement of the gate is required.

A further object of the invention is to combine the above ratchet and pawl gear with operating a mechanism controlled by a float resting on the top of he shale bed. I

A still further object of the invention is'to provide a swing hand gate operating in conjunction with the controlled rotary gate to control the depth of shale passing to the rotary gate as here Fig. 2 is a sectional end elevation of a part of the box.

Referring to the drawings, the washingbox l is of known construction and comprises perforated bed plates 2, suitably supported and upon which shale or stone 3 lies while coal 4 is shown as partially floating due to the upward current of water passing through the box. The water level isindicated at 5.

*A float ,6 resting on top of the shalebed 3 is connected by a rod '7 to one end of afloat lever 8 secured to a fulcrum shaft 9' carried in a bracket 10 mounted on the top of the box. A balance weight 11 is provided on the other end of the lever 8 and the depth of shale lying under .70 the float is shown on an indicator plate 12 by thepointed end of the lever 8. The rod '7 is guided by means such as the friction roller 13. The shale is discharged through an opening 14 and two gatesare provided for regulating the discharge. .One gate 15 is mounted .on-a rock shaft 16 adapted to be rocked by a hand lever 1'1 the shaft being mounted in the side plates 18.

The function of the gate is to regulate the depth v of shale passing to the main shale gate 19 which is a mechanicallyoperated gate of the known rotary type. 'The gate 19 is carried on a spindle 20 mounted in the side plates 18 and a ratchet wheel 21 is secured upon the end of the spindle 20 outside the box. A lever. 22 is loosely mounted on the end of the spindle 20 and carries a pawl 23 which engages with the teeth of the ratchet wheel 21. A retaining pawl 24serving to prevent any backward motion of the wheel 21 is also provided. The free end of the lever 22 is connected by a link 25 to one arm 26 of a bell crank lever whichis loosely mounted on'a rock shaft 27 carried in hearings on the top offthe box.- .A lever 28 is keyed to the shaft 27 and carries'a hinged extension piece 29 while on the opposite end of the shaft a second lever 30 issecured. The arm '31 of the bell crank lever, carries a rigid extension 32. shaped as shown adapted to engage with the extension piece 29. The engaging faces of the pieces 29, 32 are fitted with hardened steel hit and miss plates v33, 34. The shaft 27 is rocked continuously byv any suitable mechanism here. shown, as an eccentric rod 35' drivenfrom any suitable source usually theoverhead shaft of the washer box (not shown).

described automatic control mechanism is as follows It will be understood that the washing box is supplied with water and with pulsating means and with a supply of coal to be washed in any usual manner.

The depth of the shale bed 3 is first adjusted to give the desired results in'washing and the hand wheel '38 is set so as to lift the plate 33 just clear of its companion plate 34. The hit and miss plates 33 and 34 'are'now in the miss position and although the plate 33 is swinging backwards and forwards due to the action of the eccentric rod 35 acting through the shaft 27, the loosely mounted. bell crank lever 26, 31' and consequently the link 25, the lever 22 and the rotary gate 19 are at'rest, the lever 22 resting on a fixed stop 38, and no shale is being ejected from the washer box.

During the operation of coal washing, shale is being continually deposited on the bed and in consequence the float 6 is gradually forced .upwards until it reaches a point when the rising of the front end of the float lever Sand the consequent lowering of the rear end of the lever 36 with its attached link 37 causes the ,hit and miss plates 34 and 33 to make contact.

This being. so the motion of the lever 28 is transmitted to the lever 26, 31 and a vertically reciprocating motion is imparted to the link 25 which acting through the medium of the lever 22, the pawl 23 and the ratchet wheel '21 imparts .a slow rotating motion to the gate 19 thereby ejecting the surplus shale.

Conversely it follows that the ejected shale causes'a lowering of the bed 1 and the consequent lowering of the float 6 lifts the hinged piece 29 until the. catch plate 33 is again in the miss position and the rotary movement of the gate ceases, a sequenceof operations which continues indefinitely.

It will be found that under certainconditions in the event of tramp iron coming with the shale and projecting beyond the periphery of thegate the plates 39 are pushed backwards, righting themselves after the passage of the projecting pieces.

Another advantage accruing from the construction is that in the event of auto-control gear being out of commission from any cause, it is quite possible to carry on washing by hand control. Sucha contingency calls for a slight raising of the hand gate 15 and the swinging back of the plates 39. This can be accomplished by means of a lever shaft and links or by any other suitable means, the ejected shale then passing over the then stationary gate 19.

In the general construction as described above it will be noted that the mechanism is so arranged that the lever 22 and the pawl 23 operating the rotary gate are only in motion when a movement of the rotary gate is required. Such a construction ensures that the operation pawl 23 is always fully in mesh with the ratchet wheel 21 and provides for the positive engagement of in the position of the float.

the teeth when motion is transmitted to the ratchet lever 22.

It is here remarked that should the input of unwashed coal to the machine be interrupted even for lengthy periods thethen stationary gate 19 definitely prevents the egress of shale and the gradual slipping out of the bed, a not infrequent happening with a shale gate of the sliding type, becomes an impossibility.

It will be understood that while the invention has been described with reference to apparatus for washing coal it may be used for washing ores and minerals of other kinds and it is not intended to restrict its use solely to the washing of coal.

1. In a coal and mineral washing machine and in combination, a washer box, .a perforated bed for the material to be washed mounted in the box, means for admitting water to the box, a discharge opening for the shale or heavier material, a hand operated gate controlling the passage of the heavier material to the discharge opening, a rotary gate mounted on a spindle and arranged behind the hand operated gate, a ratchet wheel on said spindle, a lever on said spindle carrying a pawl engaging the ratchet wheel, a link connected to theleverand to one arm of; a bell crank lever loosely mounted on a .rock shaft, the other arm of the lever car-'- ling the passage of the heavier material to the rotary gate, a hand lever on the. spindle, and a swinging plate mounted on and depending from the spindle and clearing the periphery of the rotary gate for.v the purpose described.

3. In a coal and mineral washing machine of the type referred to and in combination,v a washer box, a perforated bed for the material to be washed mounted in thebox, means for admitting water to the box, a dischargeop'ening for the shale or heavier material, arotary, gate controlling the discharge opening and having a spindle, ratchetiandpawl mechanism for operating her on theother arm of said lever, means for rocking the rock shaft continuously, a second lever having a hinged extension member secured upon the rock shaft, and float operated means adjustably attached to the hinged extension member whereby the two extension members form a trip mechanism which engages and operates the rotary gate automatically only when movement of'the gateis required by alteration QEORGE NORTON. 

